Process of pulverizing metals.



PATENTED FEB. 3, 1903.

0. BERTOU. PROCESS OF PULVERIZING METALS.

APPLICATION FILED MAY 16, 1902.

10 MODEL.

UNTTED STATES CAMILLE BERTOU, OF PARIS,

PATENT OFFICE.

FRANCE.

PROCESS OF PULVERIZING METALS.

J"'PECIFICATION forming part of Letters Patent No. 719,725, datedFebruary 3, 1903.

Application filed May 16, 1902. Serial No. 107,654. (No specimens.)

To a whont it may concern;

Be it known that LOAMILLE BER'roU. man ufacturer, a citizen of theRepublic of France, residing at 9 Rue Riqnet, Paris,-in the Republic ofFrance, have invented a certain new and useful Process for thePulverization of Metals, of which the following is a specificamen.

If metal is liquefied by heating and intimately mixed with an elasticfluid at a high pressure and if this mixture is allowed to escape in theform of a jet into a chamber in which the ordinary pressure prevails,the elastic fluid, owing to its sudden expansion, causes thepulverization of the metal which is mixed with it. Nevertheless hithertowhen this method of effecting the pulverization of a metal has beenattempted the difflculties encountered have been such that asatisfactory result could not be attained. There are various reasons forthis, of which the following are the principal: So far the mixture of.

the metal in fusion and the elastic fluid has not been efiectedsuitably, and the jet the expansion of which produces the pulverizationhas not been successfully formed. If for this purpose thereis employed asimple injector in which the elastic fluid acts by suction, so as todraw in the fused metal and produce with it a mixture which escapes fromthis injector in the form of a jet, the operation is exceedinglydefective. This is due to the fact that the suction exerted by theclastic fluid upon the metal is not sufficient to insure a regular flowof this latter, so that there are produced in the conduit through whichthe metal flows obstructions or stoppages which impede the operation. Inaddition to this it is impossible to obtain a sufficiently finepulverization. On the other hand, if the jet consisting of the elasticfluid and the metal in fusion is merely permitted to expand in theatmosphere the metallic powder thus formed becomes oxidized in part. Inaddition to this it is necessary in order to collect it to' receive itin a very large chamber, in which it is allowed to settle; but in spiteof this the metallic particles adhere one to the other and agglomeratein such a manner that a fine powder without lumps is not obtained. Sucha powder is the only product of any real value. It is thereforenecessary to carry out diflicult and costly sifting operations in orderto effect aelassification, and so finally obtain products of which onlya portion presents the-desired degree of fineness.

The'object of this invention is to obviate these defects-that is to say,to obtain a perfeet mixture of fused metal and fluid under pressure,while preventing clogging, and to then collect the metallic powder in asmall space without possibility of oxidation or agglomeration.

In order to produce the mixture of elastic fluid and fused metal and theformation of the jet, instead of relying upon an effect of suction ofthe fluid under pressure I operate by forcing. In order to effect this,I submit the fused metal toa veryhigh pressure, which forces this metalto flow through a conduit opening into that through which the fluidunder pressure flows. The mixture which re sults from the meeting of thetwo currents escapes through a passage, upon leaving which the fluidexpands, and so produces the desired pulverization. In order to preventoxidation and agglomeration of the metallic powder so produced, While atthe same time preventing the necessity for its dispersion in a largespace, instead of merely permitting the jet to expand in the atmosphereI submit it to the action of a liquid-that is to say, it is received ina mass of water or other liquid, or such liquid is directed upon the jetitself. In either case the liquid,-owing to its contact with the finemetallic particles, instantaneously cools these particles andfacilitates their precipitation. The characteristic features of myimproved process are therefore, on the one hand, the application of apressure exerted upon the fused metal in order to cause it to flow andto mix with the elastic fluid in such a manner as to form with it a jetthe expansion of which produces pulverization and, on the other hand,the mingling of the jet of pulverized metal with water for the purposeindicated. In practice I utilize, in order to force the fused metalunder pressure, the

elastic force of the fluid itself, the mingling.

of this fluid with the metal, and its expansion, producingpulverization. The elastic fluid under pressure which I prefer to employis superheated steam; but I do not wish to limit myself to thisparticular fluid. The greater the pressure of the elastic fluid thefiner is the powder obtained. Thus in order to obtain exceedingly finepowders I employ steam at a pressure of twenty to thirty kilograms persquare centimeter.

Means for carrying out the invention is illustrated in the accompanyingdrawings, in which Figure 1 is a diagrammatic view in section of asuitable form of apparatus. Fig. 2 illustrates means for directing waterupon the jet.

a is a hermetically-closed vessel containing the fused metal and whichin the present case is heated by means of a gas-ring z.

b is a pipe through which the elastic fluid under pressure is admittedto the vessel a above the level of the metal in fusion.

0 is a conduit provided with a regulating pin-valve, through which themetal is forced, owing to the strong pressure exerted upon it by theelastic fluid.

61 is a tube which passes through the fused metal and opens in thevessel above the level of the fused metal. This tube therefore receivesthe superheated steam, which it conducts to e, where it mixes with themetal forced through the pipe 0. This mixture escapes through thepassage f. Upon leaving the passagef the jet is received in the mass ofwater contained in the vessel y, Fig. 1, or instead of this the watermay be directed upon this jet by means of an injector-nozzle X, such asthat illustrated in Fig. 2.

My process is especially applicable to the pulverization ofreadily-fusible metals, such as lead, tin, antimony, bismuth, and evenzinc and copper, and also alloys of these metals.

What I claim, and desire to secure by Letters Patent of the UnitedStates, is-

1. A process for the pulverization of readily-fusible metals, whichconsists in forcing the fused metal to flow under the action of a strongpressure exerted upon it, utilizing the elastic force of the fluiditself and forcing it to mingle with a current of elastic fluid underpressure with which it forms a jet, the sudden expansion of which causesthe pulverization of the metal.

2. A process for the pulverization of readily-fusible metal whichconsists in forcing the fused metal to flow under the action of thepressure exerted upon it by an elastic fluid under a strong pressure,utilizing the elastic force of the fluid itself, and mingling such metaland fluid forming a jet, the sudden expansion of which causes thepulverization of the metal.

3. A process for the pulverization of readily-fusible metal, consistingin forcing the fused metal to flow in a current, mingling the same witha current ofelastic fluid, utilizing the elastic force of such fluiditself to create a strong pressure,the mingling of which forms a jet andsubmitting the same at the moment of its expansion to the action of theliquid with which it mingles.

4. A process for the pulverization of readily-fusible metals, consistingin forcing the fused metal to flow in a current which mingles with acurrent of elastic fluid under strong pressure with which it forms bysudden expansion a jet upon which a current of liquid is directed, andutilizing the elastic force of said fluid itself to force said fusedmetal, substantially as specified.

5. A process for the pulverization of readily-fusible metals, consistingin forcing the fused metal to flow,under the action of a strong pressureexerted upon it, in a current which by the elastic force of a fluidmingles with such current of elastic fluid which is also under strongpressure, with which it forms a jet which is submitted to the action ofa liquid with which it mingles, substantially as specifled.

6. A process for the pulverization of readily-fusible metals, consistingin forcing the fused metal to fiow under the action ofa strong pressureexerted upon it, in a current which mingles with a current of elasticfluid, also under strong pressure, with which it forms a jet upon whichis directed a current of liquid, substantially as specified.

7. A process for the pulverization of readily-fusible metals, consistingin forcing the fused metal to flow, under the action of apressureexerted upon it by an elastic fluid under strong pressure, in a currentwhich mingles with a current of the elastic fluid, with which it forms ajet which is submitted, at the moment of its expansion, to the action ofa liquid with which it mingles, substantially as specified.

8. A process for the pulverization of readily-fusible metals, consistingin forcing the fused metal, under the action of a pressure exerted uponit by an elastic fluid under strong pressure, to flow in a current whichmingles with a current of the said elastic fluid, with which it forms ajet upon which is directed CAMILLE BERTOU.

Witnesses:

EDWARD P. MAOLEAN, HENRY A. BERTIN.

